/*=========================================================================
 *
 *  Copyright RTK Consortium
 *
 *  Licensed under the Apache License, Version 2.0 (the "License");
 *  you may not use this file except in compliance with the License.
 *  You may obtain a copy of the License at
 *
 *         http://www.apache.org/licenses/LICENSE-2.0.txt
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 *
 *=========================================================================*/
#ifndef rtkProjectionsRegionConstIteratorRayBased_hxx
#define rtkProjectionsRegionConstIteratorRayBased_hxx

#include "rtkProjectionsRegionConstIteratorRayBased.h"
#include "rtkProjectionsRegionConstIteratorRayBasedParallel.h"
#include "rtkProjectionsRegionConstIteratorRayBasedWithFlatPanel.h"
#include "rtkProjectionsRegionConstIteratorRayBasedWithCylindricalPanel.h"
#include "rtkHomogeneousMatrix.h"
#include "rtkMacro.h"

namespace rtk
{
template <typename TImage>
ProjectionsRegionConstIteratorRayBased<TImage>::ProjectionsRegionConstIteratorRayBased(
  const TImage *                           ptr,
  const RegionType &                       region,
  const ThreeDCircularProjectionGeometry * geometry,
  const MatrixType &                       postMat)
  : itk::ImageConstIteratorWithIndex<TImage>(ptr, region)
  , m_Geometry(geometry)
  , m_PostMultiplyMatrix(postMat)
{}

template <typename TImage>
ProjectionsRegionConstIteratorRayBased<TImage> &
ProjectionsRegionConstIteratorRayBased<TImage>::operator++()
{
  // This code is copy pasted from itkProjectionsRegionConstIteratorRayBased since
  // operators are not virtual.
  this->m_Remaining = false;
  unsigned int in = 0;
  for (in = 0; in < TImage::ImageDimension; in++)
  {
    this->m_PositionIndex[in]++;
    if (this->m_PositionIndex[in] < this->m_EndIndex[in])
    {
      this->m_Position += this->m_OffsetTable[in];
      this->m_Remaining = true;
      break;
    }
    else
    {
      this->m_Position -= this->m_OffsetTable[in] * (static_cast<OffsetValueType>(this->m_Region.GetSize()[in]) - 1);
      this->m_PositionIndex[in] = this->m_BeginIndex[in];
    }
  }

  if (!this->m_Remaining) // It will not advance here otherwise
  {
    this->m_Position = this->m_End;
    return *this;
  }

  if (in == 2)
  {
    NewProjection();
  }
  NewPixel();

  return *this;
}

template <typename TImage>
ProjectionsRegionConstIteratorRayBased<TImage> *
ProjectionsRegionConstIteratorRayBased<TImage>::New(const TImage *                           ptr,
                                                    const RegionType &                       region,
                                                    const ThreeDCircularProjectionGeometry * geometry,
                                                    const MatrixType &                       postMat)
{
  if (geometry->GetSourceToDetectorDistances().empty())
  {
    itkGenericExceptionMacro(<< "Geometry is empty, cannot determine iterator type.");
  }
  if (geometry->GetSourceToDetectorDistances()[0] == 0.)
  {
    if (geometry->GetRadiusCylindricalDetector() != 0.)
    {
      itkGenericExceptionMacro(<< "Parallel geometry assumes a flat panel detector.");
    }
    using IteratorType = ProjectionsRegionConstIteratorRayBasedParallel<TImage>;
    return new IteratorType(ptr, region, geometry, postMat);
  }
  else if (geometry->GetRadiusCylindricalDetector() == 0.)
  {
    using IteratorType = ProjectionsRegionConstIteratorRayBasedWithFlatPanel<TImage>;
    return new IteratorType(ptr, region, geometry, postMat);
  }
  else
  {
    using IteratorType = ProjectionsRegionConstIteratorRayBasedWithCylindricalPanel<TImage>;
    return new IteratorType(ptr, region, geometry, postMat);
  }
}

template <typename TImage>
ProjectionsRegionConstIteratorRayBased<TImage> *
ProjectionsRegionConstIteratorRayBased<TImage>::New(const TImage *                           ptr,
                                                    const RegionType &                       region,
                                                    const ThreeDCircularProjectionGeometry * geometry,
                                                    const HomogeneousMatrixType &            postMat)
{
  MatrixType pm;
  for (unsigned int i = 0; i < MatrixType::RowDimensions; i++)
    for (unsigned int j = 0; j < MatrixType::ColumnDimensions; j++)
      pm[i][j] = postMat[i][j];
  return New(ptr, region, geometry, pm);
}

template <class TImage>
rtk::ProjectionsRegionConstIteratorRayBased<TImage> *
ProjectionsRegionConstIteratorRayBased<TImage>::New(const TImage *                           ptr,
                                                    const RegionType &                       region,
                                                    const ThreeDCircularProjectionGeometry * geometry)
{
  MatrixType postMat;
  postMat.SetIdentity();
  return New(ptr, region, geometry, postMat);
}

} // namespace rtk

#endif
